Figure 2.

COX11 variation is associated with decreased respiration‐derived ATP levels, which can be restored with CoQ_10. ATP levels were measured by flow cytometry after 6 h of metabolic substrate in patient X1 (COX11) and control fibroblasts expressing a genetically encoded FRET‐based ATP sensor. Basal ATP levels were similar between all conditions. Respiration‐only ATP levels were normalized within each cell line to basal and depleted conditions. Patient XI (COX11) and control fibroblast ATP levels remained high with unrestricted basal metabolism. When metabolism was restricted to respiration‐only by addition of 10 mM 2‐deoxy‐d‐glucose, ATP levels dropped in patient cells that were treated with the vehicle, while patient XI (COX11) cells maintained higher levels of ATP with CoQ₁₀ treatment. Data show mean ± SEM; n= 2−8 replicates of at least 300 cells per condition, compiled from two independent experiments. ***p< 0.001, *<0.05 by two‐way analysis of variance with Tukey's multiple comparisons test. ATP adenosine triphosphate; FRET, fluorescence resonance energy transfer.